I have read that pressing c2 button then turning the camera setting dial should bring up a green horizontal line. Turning the dial will adjust the gimbal.
I cant get that to work.

Where did you read that?

If you do a youtube search for mavic pro horizon tilt you will see a few examples

Yes, but I find this very inconsistent and useless.  If you make sure you take off from pretty level ground & all your sensor values are very low, you shouldn't have to ever mess with it.  I haven't on my Mavic or P4P.  I only tried out that button combo, then zeroed out.

fansc73d3cec Posted at 2016-12-22 19:52
If you do a youtube search for mavic pro horizon tilt you will see a few examples

Interesting. I was only able to find one video for the Mavic that showed that and it was from a month ago. I tried it out and it does not work which leads me to believe either a firmware update or an app update killed that option. Not sure why they would do that since we've asked them to give us that option like the Phantoms have.

DRONE-flies-YOU Posted at 2016-12-22 20:11
Yes, but I find this very inconsistent and useless.  If you make sure you take off from pretty level ground & all your sensor values are very low, you shouldn't have to ever mess with it.  I haven't on my Mavic or P4P.  I only tried out that button combo, then zeroed out.

90% of the time my Mavic has a tilted horizon so for me this would be very useful since going into the settings the adjust the roll is pretty inconvenient.

trance728- Posted at 2016-12-22 18:24
90% of the time my Mavic has a tilted horizon so for me this would be very useful since going into the settings the adjust the roll is pretty inconvenient.

Dang that stinks.  

Perhaps try the auto gimbal calibration.  I did that on my P4P just to "try it out" but my horizon was still level.  Use a level and make sure the "adjust roll" is zeroed prior to calibrating.

Could you please clarify you current firmware version? And please make a short video of this issue.